Computer based control systems are widely used in a number of different industrial environments, such as for instance a pulp and paper process, a steel rolling mill, a process in an oil and gas production installation or in a refinery, and in an installation for producing, generating or distributing electrical power. Such process control systems gather and contain information about plant equipment, current and historic process data, trends, etc to carry out supervision and control of processes, industrial plants and production facilities. This information is typically provided by the control system and usually in the form of one or more distributed control systems (DCS) and/or supervisory control and data acquisition (SCADA) systems.
The process control information is typically presented to the operators by a display screen showing a number of different process graphics that each presents process data (measurements, values), tag identifiers, equipment ID, alarm status, connections between plant equipment, etc for a given process or process section. As more and more data is presented to the operators, the number of process graphic in a process control system increases and visual user interfaces often hold a great deal of information. WO2005/109122 entitled Graphic element with multiple visualizations in a process environment, and assigned to Fisher Rosemount Systems Inc., describes a system in which smart graphic elements are provided for use as portions or components of one or more graphic displays. According to the Abstract, the smart graphic elements may be executed in a process plant to display information to users about the process plant environment, such as the current state of devices within the process plant. Each of the graphic elements is an executable object that includes a property or a variable that may be bound to an associated process entity, like a field device, and that includes multiple visualizations, each of which may be used to graphically depict the associated process entity on a user interface when the graphic element is executed as part of the graphic display. Any of the graphic element visualizations may be used in any particular graphic display and the same graphic display may use different ones of the visualizations at different times.
The work of an operator supervising a process includes the important functions of supervising the various parts of a process, and taking control actions when necessary. The main functions used by the operators are typically alarm management, trends and process graphics. An important functionality in the control system is navigation and another important aspect of that is visualization of system status and to highlight data that has provoked an abnormal condition. However, along with increased access to information, the task of finding the relevant technical information for a given technical subject or condition in a large information space is further complicated by the fact that in some situations the operator often has limited time available to make a decision. The significance of the information available will vary with the current situation. That is, users of industrial control systems have to deal at least in part with a problem of what is relevant in a given context, context sensitivity, as in some contexts certain information will be essential and in other contexts irrelevant.
Operators often find it difficult to navigate from one process graphic to another in order to find the information they seek. New operators spend great amounts of time getting to know the process graphics, to learn which information is located where and especially how to move from viewing an equipment or process in one process graphic to find and view a relevant equipment or process monitored and controlled by another process graphic. Furthermore, viewing several process graphics at the same time is technically possible today, but is difficult to use in practice. The most used solution for this is to have several monitors/windows and navigate each of these independently. It is common to find several display screens arranged on an operator desk, so that the operator has several views/displays open in front of him/her in order be able to view or find the desired information quickly.
However, even when using multiple screens, there is often no sense of context. When operators are looking at a display of one particular process graphic, it is often not possible to know where in the hierarchy of process displays the user currently is, and to which other process graphics they should go to in order to follow up on information or an event in the current process graphic on the current display. The inventors have identified that there is a need for a way to quickly navigate from one process graphic display to another in a logical manner while still keeping an overview of the process in sight.